I don't think you fully comprehend The New York Times Co. v. Sullivan
You cannot knowingly print deliberate falsehoods. It is apparent from the posting on Breitbard, that the publish knew, or should reasonably known, that what it was printing about Palin contained unsubstantiated malicious rumors.
PS: George Bush could own CBS, Dan Rather and Mary Mapes, but who’d want them? He shudda sued, on principle.